Wireless sensors system and method of using same

ABSTRACT

An apparatus, system, and methods for measuring environmental parameters are disclosed. The apparatus, system, and methods can be used for a variety of applications, including HVAC air balancing and building commissioning. The system includes a variety of wireless sensing modules and wearable modules for control, display, and storage. Parameters measured include air and water temperature, pressure, velocity, and flow. Also included are sensors for light intensity, CO concentrations, and CO2 concentrations.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Provisional Patent ApplicationNo. 61/401,336, filed Aug. 11, 2010, entitled Wearable WirelessInstrument System.

This application claims the benefit of Provisional Patent ApplicationNo. 61/463,549, filed Feb. 19, 2011, entitled System of Wireless Sensorswith Wearable Controller.

FIELD OF THE INVENTION

The present disclosure generally relates to measuring environmentalparameters such as temperature, humidity, and pressure. Moreparticularly, the disclosure relates to system and method for measuringenvironmental parameters and wirelessly transmitting information to adisplay device.

BACKGROUND OF THE INVENTION 1. Problems

Instruments are often used to measure air and water parameters such astemperature, humidity, pressure, air velocity, airflow, and many otherenvironmental parameters. These measurements take place in buildings,factories, outdoor weather stations, and other locations. Instrumentsmay be rack-mount, desk mount, mobile/handheld, or other.

A typical instrument consists of a plastic case enclosing a printedcircuit board with microprocessor-controlled electronics, memory, one ormore sensors, and a display. The sensors are often in a wand-shapedprobe. Various probes, large and small, are designed to collectenvironmental samples for sensing, measurement, display, and storage.When using this type of instrument, a user has both of his handsoccupied, one to hold the meter, and one to hold the probe and extend itto the location of interest, such that a user's hands are not availablefor other tasks. Cables, wires, and/or tubes typically dangle betweenthe probe and the meter.

For Heating, Ventilation, Air Conditioning, and Refrigeration (HVAC)applications, engineers and technicians who work in buildings deal withmany different types of instruments. There are building automationsystems (BAS), fire safety systems, occupancy detection and security,permanently installed instruments such as pressure, temperature,humidity, and airflow, with some nearby and some remote sensors, andportable instruments for such parameters as temperature, pressure,humidity, sound/noise, light intensity, carbon dioxide, velocity, flow,and others. As engineers and technicians move throughout the structureto solve problems, they often lack access to required information, andmust either move to a central location for access to data, or must carrya variety of instruments with them. Lacking is an overall system forquick access to desired information.

Engineers and technicians commonly require two types of measurements.One is immediate feedback when finding and/or solving a problem, as whenmeasuring the temperature of air being supplied at a diffuser. Thesecond is a series of measurements at regular intervals from one or manylocations, for comparison and contrast of parameters that may indicateproblems that occur over time.

Measurement problems are important to the HVAC industry. Measurementdisputes are often at the heart of conflicts over HVAC performanceissues such as uncomfortable buildings, inefficient energy performance,and inability to maintain specified parameters such as adequate positivepressure in hospital operating rooms. These conflicts frequently resultin anger, confusion, disputes, cancelled contracts, lawsuits, mediation,and unhappy building owners, tenants, and workers. Contributing to theseconflicts is that measurements of HVAC-related building parameters suchas air and water temperature, humidity, pressure, velocity, and flow areperceived to be inaccurate and unreliable, so dissatisfied parties oftenchallenge their validity. Accordingly, an improved system and methodthat improves the accuracy and speed of measuring building parametersand the safety with which they are measured by technicians are desired.

Flow, airflow, and water flow are industry terms that relate to thevolumetric rate of fluid flow expressed in units such as cubic feet perminute (CFM) or gallons per minute. Airflow is usually not measureddirectly. It is usually calculated by measuring the velocity of air atmultiple points in a cross-sectional plane, calculating an averagevelocity at the plane, and then multiplying by the known area of thecross-section. The plane where measurement takes place might be acrossan air duct, in a duct-shaped probe like a capture hood, or at theopening of a fume hood, door, or window.

These are long standing problems in several different measurementapplications related to HVAC.

Exemplary Problem 1. Wasteful Back and Forth Travel.

Technicians are concerned with the occupied spaces and the systemcontrols that are spread all over the building, from the facilitiesspace with the fan, coils, pumps, pipe, compressor, and/or evaporationtower, through the duct system to the occupied spaces. In many cases thepoint of interest to an operator or technician is some distance removedfrom the forces or controls that cause the conditions at the point ofinterest. To adjust the controls for improved operation requires a lotof back and forth movement during a repetitious cycle of measurementsand adjustments. They must measure at one location, then move to anotherlocation to effect a repair or adjustment. Then they must return to theoriginal location to measure the impact of the change. This wastes timeand leads to approximations. What is needed is real-time data at thepoint of control, so changes can be readily evaluated and adjustmentsmade precisely as specified.

Exemplary Problem 2. Poor Communication within Teams.

A second problem of conventional practice in HVAC measurements relatesto technicians who work in teams of two or more. Measurements areusually taken by one person. Team members who need the information mustreceive it from the one who took the reading, usually by speaking,shouting, or walking to a conference, or sometimes via walkie-talkie orcell phone.

Exemplary Problem 3. Instrument Limitations.

A third problem with existing instruments is that they provide limitedinformation with each measurement. For instance, during a velocitytraverse of an HVAC duct, the technician may need to record a series ofair velocity measurements, plus the air temperature, air humidity,barometric pressure, and the duct static pressure. The meter he uses maydisplay only one of these parameters at a time. Further, he may have tochange the setup of the meter between measurements to acquire all of thenecessary information. Accordingly, an improved system and method toprovide technicians with more of the information relating to aparticular application are desirable.

One reason for this problem is that general-purpose instruments arebeing used for applications that are specific to operations such as airbalancing. For instance, a differential pressure meter is attached viarubber tubes to a Pitot tube, and the combination used to determine theair velocity in the duct. It is desirable to have a tool designedspecifically for HVAC applications such as duct velocity traverse.

Engineers and technicians do not have one system of convenient access torequired information. Instead, they often use a wide variety ofinstruments, including BAS, temperature meters, humidity meters, airpressure meters, water pressure meters, air flow meters, water flowmeters, etc. It is desirable to have the capability to quickly accessany required measurement as they move throughout a building to find andfix problems. It is desirable to have a system and method that allowengineers and technicians to measure immediately and interactively,while also providing means to datalog the same measurement types at thesame locations at regular intervals over a period of time.

Exemplary Problem 4. Instrument Style.

A fourth problem in conventional practice has to do with the size andshape of instruments and the intended method for taking measurements.Many instruments are designed in the form of a hand-held probe attachedwith a coiled cord to a handheld meter. Taking a measurement occupies atechnician such that he cannot do anything else with his hands at thesame time. In connection with the measurements taken, it is oftennecessary for a technician to use his hands to climb a ladder, drillholes, screw or unscrew, or move a lever. A technician may have to setdown an instrument in order to effect a repair or make an adjustment,and in so doing will lose sight of the meter readings. The existing typeof instrument is clearly cumbersome in this context. It is desirable tohave instruments that are relatively small, relatively light in weight,and easy to manipulate in the environment of interest. I

Exemplary Problem 5. Instrument Size and Weight.

Airflow capture hoods are used to collect the air being supplied bydiffusers. One popular capture hood weighs 10 pounds and must often beheld tightly against a ceiling diffuser. If the ceiling is high, thetechnician must employ a ladder. This type of procedure is difficult formost people to perform properly hour after hour, day after day. Fatigue,strain, and injuries are common. It is therefore desirable to haveinstruments that are relatively small, relatively light in weight, andeasy to manipulate in the environment of interest.

Exemplary Problem 6. Accuracy and Reliability

As a result of Problems 1 through 5, measurements are often performedtoo quickly, improperly, inaccurately, or not at all, due to short cutstaken by technicians under stress. For instance, a technician whorealizes that a measurement is likely because of circumstances to beinaccurate or unrepresentative is more likely to compromise, estimate,or skip the measurement. It is desirable to have instruments that arequick and easy to use and that can be trusted to achieve an accurateresult.

Exemplary Problem 7. Manpower.

Current practice is to use two-man teams, for some of the reasons listedabove: safety; heavy, cumbersome instruments; working above the groundon ladders or scaffold; needing to be in two places for measurements andcontrol adjustments. Accordingly, systems and methods that require lessmanpower are desired.

INDUSTRY APPLICATIONS

The following use cases are some industry procedures that illustrate thelong standing problems mentioned above.

Set Point of Duct Static Pressure

In HVAC duct systems it is important to maintain duct static pressuresetpoints at various locations in a duct system in order to maintainairflow through the duct and diffusers. For instance, a buildingengineer might specify that the fan generate a duct pressure that is 3inches of water column above the ambient pressure in the building(static pressure), that the secondary supply air ducts that feed eachfloor be maintained at 2.5 inches of water column, and that the systemof valves and dampers be adjusted such that the most remote air diffuserwill be supplied air at a pressure of at least 0.5 inches of watercolumn. If pressure is too low, the diffusers will not distributeconditioned air as designed and building comfort will suffer. Ifpressure is too high, energy is wasted by running the fan too fast. Theelectric power used increases at the cube of the duct pressure increase.For instance, if the fan speed is increased to raise the remote ductpressure to 0.55 inches, only 10% higher than required, the fan will use30% more electric power than required. (The calculation has the form of1.1×1.1×1.1==1.3.)

Current procedure requires a technician to measure the pressure, thenmove through the building to adjust the fan and the dampers. He thenreturns to measure pressure again. This cycle of measurement andadjustment will be repeated until the specified result is achieved.Sometimes the fan is a long distance from the point being measured, andon a different floor. This repetitive procedure requires a lot of timeand effort, and leads to the technician settling for some safeguard-banded pressure instead of achieving the precise result desired.This is one of the main sources of wasted energy in buildings. It isdesirable for applications like this to provide a technician with a animproved system and method for making measurements at the point ofinterest, and delivering results continuously to him where and when heis making the adjustment at the point of control.

Setting Outside Air Ventilation Controls

One of the most important functions in HVAC is to provide adequateventilation, which is done by bringing in fresh air to replace used airthat is infused with odors, body moisture, carbon dioxide, and otherproducts of the indoor environment. This is a health issue, not just acomfort issue, and is strictly regulated. The volume of outside airneeded is calculated according to industry formulas. Then the outsideair dampers and control fans are adjusted by a degree estimated toachieve the correct volume.

This procedure often involves the measurement of several temperatures:outside air, indoor supply air, indoor return air, and the air insidethe mixing chamber. The temperature in the mixing chamber is related tothe temperature of return air and outside air, and the volumes of each.Adequate ventilation can be determined by measuring and comparing thedifferent temperatures. Adjustments are made, and then the fourtemperatures are measured again. This is repeated until the mixed airtemperature reaches a specific function of outside air and return airtemperatures. Needed is a way to measure all four of these temperaturesconcurrently, and provide them in real time to the technician at thepoint of control, so he can quickly see the result of his adjustment.

Damper Setting and Proportional Balancing Method

Two technicians generally work together to adjust dampers to set airflowthrough supply diffusers to match specifications. One tech lifts up andholds a capture hood airflow probe against the diffuser, which isusually on the ceiling. He reads a meter attached to the capture hood.He calls out the reading. The second technician climbs a ladder andlocates the damper adjustment above the ceiling tiles. He adjusts thedamper until the measurement called out meets the specification. Neededis a way for the person doing the adjusting to be able to see theresults of the adjustment in real time.

The meter must measure the temperature of the supply air in order tomake an accurate reading. However, it takes a long time for temperatureprobes to properly register the actual temperature of air coming out ofthe duct, so technicians often ignore this requirement. Needed are meansfor quickly measuring the actual air temperature and using it to improvethe accuracy of the measured airflow.

Also needed is a way for one person instead of two to perform this task.A stand or jack can be employed to hold the capture hood against aceiling diffuser. This helps prevent the heavy and bulky hood fromlosing a seal, and it prevents weariness and injury to the operator.However, it is still necessary for the adjustor to have the measurementshouted over to him, or, if working alone, for him to leave the damper,climb down from the damper, walk to the capture hood, see the result onthe meter, and return to the damper to make another adjustment.

A related industry method is the Proportional Balancing Method.Specifications often require that supply air diffusers be adjusted sothat their airflows are all the same percentage of the specifiedairflow. For instance, if there are three diffusers, and the airavailable is 10% less than specified, then each air diffuser should beset to 90% of the specified flow. If the specified flows were 300, 200,and 100 cubic feet per minute (DFM), then the post-adjustmentmeasurements should be 270, 180, and 90 CFM. However, duct systems withdampers and supply diffusers and return grills have paths to resistanceof airflow that are interrelated. That is, if one path is made moreresistant to airflow by adjustment of a damper, the air adjusts and goessomewhere else. This makes it difficult to set dampers the way theyshould be set. Usually the diffuser furthest from the fan is set byadjusting its damper. Then a second damper is adjusted. Then, the firstdiffuser must be measured again to determine if the second adjustmentcaused such a change in duct airflow distribution that the firstdiffuser airflow became out of range. The two dampers are adjusted againuntil they are both in spec. Then a third damper is adjusted. Thiscontinues until all diffusers on the same branch of the duct system arewithin the specified range. This takes a long time, with many repeatedmeasurements. Each diffuser must be measured independently, one at atime, despite the fact that they are part of a connected andinterdependent system. This method is repetitious and wastes time. Itleads to compromise and non-ideal outcomes. What is needed is to see theeffect of changes in real time.

Evaluation of Thermal Transfer Coil Efficiency

It is often important to measure the moisture content of air in ducts. Acritical HVAC function is thermal energy transfer via coils. Forinstance, energy is used to remove moisture and cool air from outsidethat enters hot and humid. HVAC technicians must measure the temperatureand moisture content of air before and after it is exposed to the bankof coils in order to determine whether the system is performingproperly. Then the system is exercised to vary the load on the coilswhile measurements are taken. Needed for this application are means ofconcurrently viewing the incoming air temperature and humidity as wellas the outgoing air temperature and humidity.

Water-Side Balancing

In HVAC machine rooms there are pipes running to and from the chillers,evaporators, pumps, and valves. It is necessary to measure watertemperature and pressure in various places. These measurements arerelated to each other. At present is it time consuming to make iterativemeasurements between many adjustments to pump speeds and valve setting.Needed are means to see a variety of water pressures, temperatures, andwater flows concurrently.

Velocity Traverse of Air Duct

The volume of air moving through a system of ducts is a frequentlyrequired figure in HVAC. System designers specify the aircharacteristics at specific locations throughout the duct system:leaving the fan, passing through filters and coils, delivered to themain duct on each floor, branch ducts, and finally supply air diffusers.The same is true for the return path to the fan intake, which begins atreturn air grilles in the occupied spaces, then past return air fans anddampers, mixing chambers where outside air enters, and into the main airhandler intake. At each of these key points in the system, air balancersmeasure airflow volume, temperature, humidity, and duct static pressure.

Airflow volume is not measured directly in a duct. Instead, the averagevelocity of the air is determined and multiplied by the cross-sectionalarea of a plane across the duct. Since the velocity of air variessignificantly over such a cross-sectional plane, an average velocitymust be determined by measuring many different locations in thecross-sectional plane, and then averaging those values. The industry hasderived standards for the locations to be measured, that are specifiedin terms of the distance from the duct walls.

A technician first measures the length and width of a rectangular duct,or the diameter of a round duct, and calculates the cross-sectionalarea, adjusting for the thickness of the duct walls and any insulationor other internal obstructions. Then he consults a table provided by anengineering society such as ASHRAE for the locations of the points in amatrix on the duct cross-sectional plane. The technician drills holes inthe duct to allow the Pitot tube to be positioned at the each point inthe matrix. It is convenient to think about horizontal and verticalplanes across the duct. The technician marks his probe with tape so hecan see how far into the duct to insert it to reach each traverse point.Then he makes a velocity measurement at each traverse point, one afterthe other, recording or storing each reading as he goes. In most casesit is necessary to measure between 16 and 150 different traverse points.This is a laborious and error-prone operation.

During a duct velocity traverse, a technician stands high on a ladderwith his head in the dark space above the ceiling tiles. Withtraditional equipment, he holds a meter in one hand and a velocity probesuch as a Pitot tube in the other hand. Between the meter and the Pitottube are rubber hoses that dangle down and are prone to getting caughton projections. The hoses are also prone to swinging during measurement,which can affect the accuracy of the measurement.

A proper velocity measurement also requires determining the air density.Density in turn requires barometric air pressure, temperature, and ifpossible, humidity. Barometric pressure is easily measured inside themeter and is not a problem. Temperature and humidity present anotherproblem for a technician. Already burdened by meter, probe, and danglingtubes, he must manipulate a temperature probe from the meter into theduct and keep it lodged there while performing the 16 to 150 separatevelocity measurements mentioned above.

Once the velocity traverse has been completed and the Pitot tubewithdrawn from the duct, a technician performs a separate setup toprepare to measure duct static pressure. A traditional meter must beremoved from a Pitot velocity mode and placed into a differentialpressure measurement mode. Then the user changes the hose connectionsbetween the Pitot tube and the meter. Finally, the user reinserts thePitot tube into the duct and performs the static pressure measurement.

In summary, the airflow, velocity, temperature, and pressuremeasurements required are difficult and time consuming to obtain usingtraditional instruments and methods. Such a measurement process mayrequire three different duct insertions, three different measurementmodes on the meter, and two different hose configurations. The bulkymeter may weigh a few pounds, and the user may have difficultymanipulating it with one hand to press the control keys whilemanipulating the Pitot tube with the other hand and keeping the tubesand temperature probe from swinging and getting tangled.

DESCRIPTION OF RELATED ART Existing Products and Technologies

Recently some wireless meters have appeared (e.g., Testo) eliminatingthe conventional coiled cable between the probe and the main body of themeter. However, one hand is still necessary to hold the meter, andanother is required to hold the sensing probe. The sensing probes arestill as large and ungainly as conventional instruments. They can beplaced and left on a desk or file cabinet or floor, but are difficult toplace at the point of interest for HVAC technicians, such as slotted airdiffusers or water pipes.

Another type of wireless device has been used in HVAC applications. Thisis a wireless sensor network for datalogging, collecting environmentaldata at regular intervals. For example, at intervals of 10 seconds orone minute, a sensor makes a measurement and transmits it wirelessly toa stationary data collection and storage point. Once in a while thecollected and stored data can be loaded onto a computer for analysis.The network data collector's memory is erased and a new set of datacollection begins. This type of system is used to monitor buildings andfactories. An example of this type of instrument is Wizard from Dickson.While useful for some tasks, the system has drawbacks. It requires apersonal computer to display the results, so it is cumbersome to movearound a building. The sensor modules are shaped for mounting on a deskor file cabinet or other flat place, but are not convenient for airdiffusers and pipes.

In a quite different industry, medical monitoring of vital signs,wearable wireless instruments have appeared. These collect measurementssuch as blood pressure or pulse rate and wirelessly transmit the resultsto a nearby data collector or to the wrist of the user. From thereresults can be viewed or sent to a monitoring system for review oralarm. A related module might sound an alarm to the person wearing thesensors to alert them to excessively high blood pressure or similarproblem. However, this type of instrument is not useful for finding andfixing HVAC problems, because it does not provide for remote sensorsmeasuring environmental conditions.

Another interesting wireless application is wrist-mounted displays forrunners and other athletes that show data from sensors mounted in theirshoes or on their bodies to provide a measure of their performance.These systems lack remote sensors that measure environmental parameters,as well as other features that are applicable to HVAC and otherindustrial applications.

Problem Summary

To summarize the general problems with traditional instruments andmethods, they limit the productivity of technicians by being heavy,cumbersome, by not measuring all of the required parameterssimultaneously, by restricting the availability of measurement dataamong team members, and by forcing repeated movement between the pointsof cause and effect. Measurement procedures take much longer thandesirable. Time is wasted. These problems lead to short cuts bytechnicians, which in turn product inaccurate or misleading measurementsthat have little credibility among industry peers.

Accordingly, improved apparatus, methods, and systems for measurement ofenvironmental parameters are desired.

SUMMARY OF THE INVENTION

The present invention generally relates to an apparatus, system, andmethods for measuring environmental characteristics of fluids, such asair and water. While the ways in which the invention address the variousdrawbacks of the prior art are addressed in more detail below, ingeneral, the apparatus, system, and methods provide means and methodsfor collecting desired environmental measurements from many locationsand conveniently presenting the desired measurement results in realtime.

In accordance with various exemplary embodiments of the invention, asystem for wireless measurements includes a variety of sensors to makein-situ measurements and transmit the results to the user where they aredisplayed and stored, e.g., via wearable modules, to free the hands ofthe user to make control adjustments and deal with tools.

In accordance with various exemplary embodiments of the invention, thepresent invention provides a system including applications-specificwireless sensing modules for accurate, in-situ measurement of buildingparameters, and wearable instrument components for real-time access viavisual display and/or audible words, by technicians for beneficial useat the location of adjustment and control. The present invention is aninstrumentation system of distributed modules with various functions.Each module may be specially designed for a specific HVAC-relatedmeasurement function. Communication between modules may be via wireand/or RF wireless.

Unexpected benefits are derived from distributing the functional aspectsof a measurement system to the location where they are best performed.Sensing and measurement may be done on a continuous schedule at thepoint of interest, in-situ, and does not burden the technician afterplacement. Results arrive regularly to a location where a technician caneasily view it and act on it. Different results from different locationsare presented together to improve understanding of the environment andquicker technician actions. Results are shared among all team membersfor optimum efficiency, and team members may communicate via theoptional integrated walkie-talkie feature.

Improvements include better safety, reduced technician time, betteraccuracy, and less expensive instrumentation.

Exemplary system communication and control modules include:

-   Control-   Display-   Head mount display-   Head mount audio-   Thumbswitch-   Repeater-   Computer/PDA interface-   Web access

Sensor modules include the following types:

-   Temperature types for air, water, and surfaces.-   Humidity types.-   Pressure types for air.-   Pressure types for water-   Air velocity-   Airflow-   CO concentration-   CO2 concentration-   Light intensity-   RPM for fans/motors-   Inclinometers for damper vane position/angle

Instrument interface modules provide interfaces to existing instrumentsand sensors such as electric utility meters and ultrasonic flow metersusing one or more of these methods:

-   Digital communication stream-   Pulse counter-   Analog 4-20 mA current loop.-   Analog voltage 0-5 v and 0-10 v.

The present invention includes this new apparatus:

-   Light-weight capture hood.

The present invention includes these improved methods:

-   Adjustment of dampers for adequate ventilation.-   Adjustment of duct static pressure setpoint.-   Duct velocity traverse.-   Water-side balancing.-   Adjustment of Room-to-Room pressures.-   Proportional balance.

The present invention provides a technician with freedom of movementwhile viewing measurement data on his wrist. He can see the result ofhis adjustments in real time and store measurement values while movingaround.

A display format is provided to compare and contrast two or moredifferent measurements from different locations. A personal computer mayserve as a control module with an appropriate communication moduleplugged into its port.

The present invention allows multiple team members to share measurementresults via a wearable module, which promotes better teamwork and higherproductivity. Optional walkie-talkie's are built into the controlmodules to provide voice communication via the same communication methodused for measurement data.

These system capabilities make possible new, better methods forindustrial repairs and adjustments. For instance, they eliminate theback-and-forth nature of many industrial operations where the point ofinterest is different from the point of control. Instead of a long cyclemeasurement/adjustment/measurement/etc., a real-time stream ofmeasurements is available at the point where the adjustment is beingmade, saving time and facilitating a more precise final result.

The distributed nature of the instrument in the present invention makesit possible for a technician to make the necessary measurements at thelocation of interest, transmit the measurements quickly to the locationwhere they are most needed for decisions and adjustments, which may be afew feet or hundreds of feet away. The measurement results can bedisplayed on a wrist-mounted module, a head-mounted module for heads-upviewing, or annunciated in the user's ear. The user's hands during thisprocess are free for tasks instead of being occupied by instruments.

Various embodiments of the present invention combine two operating modesthat were previously only available in different instruments. One is adiagnostic or debugging mode used by a technician to promptly discoverand fix problems. The other is a monitoring or datalogging mode whichcollects measurements regularly from distributed sensors over a periodof hours, days, or weeks. The data is analyzed later, usually plottedagainst time to show relationships between events. A related and uniquecapability is that the present invention allows a mobile module todisplay the results in a diagnostic mode from sensors that are also atthe same time part of a datalogging network.

The present invention also makes existing instruments more useful inseveral ways. Each result may be sent from the location of measurementto the location where an adjustment is necessary. The control moduleprovides a very large memory for storing measurements and providesstatistics that are often missing in other instruments. Measurements maybe stored and compared along the same timeline as measurements fromdifferent instruments. The measurement data can be shared by multipletechnicians in real time.

Sensor modules are sensing instrument probes that measure environmentalparameters such as temperature, humidity, and pressure. Sensor modulesare provided in accordance with various aspects of the presentinvention. Exemplary sensor modules include handles and means ofattachment to industrial equipment so they do not have to be held by atechnician when readings are being taken. Each of the sensor modules isdesigned to be small and easy to handle and be placed at a particularpoint of interest where the best accuracy can be obtained, and they canthen be left, in-situ, performing continuous measurements that are sentto the technician wirelessly. They are designed to dramatically speed upa particular type of measurement and improve accuracy. They are designedto overcome the problems inherent in current industry practice asdescribed above.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the drawing figures, wherein like numeralsdenote like elements and wherein:

FIG. 1 illustrates the system form in accordance with exemplaryembodiments of the invention.

FIG. 2 illustrates the wearable control module in accordance withexemplary embodiments of the invention.

FIG. 3 illustrates the thumbswitch in accordance with exemplaryembodiments of the invention.

FIG. 4 illustrates head-mountable communication in accordance withexemplary embodiments of the invention.

FIG. 5 illustrates the use of repeater modules for extending the usablesystem range in accordance with exemplary embodiments of the invention.

FIG. 6 illustrates repeater modules in accordance with exemplaryembodiments of the invention.

FIG. 7 illustrates an application for a system of temperature andhumidity modules in accordance with exemplary embodiments of theinvention.

FIG. 8 illustrates a multitude of measurement result display formats inaccordance with exemplary embodiments of the invention.

FIG. 9 illustrates some types of temperature modules in accordance withexemplary embodiments of the invention.

FIG. 10 illustrates humidity sensor modules in accordance with exemplaryembodiments of the invention.

FIG. 11 illustrates differential air pressure sensors in accordance withexemplary embodiments of the invention.

FIG. 12 illustrates measurement of water pressure and temperature inaccordance with exemplary embodiments of the invention.

FIG. 13 illustrates areas of different pressures in a cleanroom.

FIG. 14 illustrates a system of duct air sensors in accordance withexemplary embodiments of the invention.

FIG. 15 illustrates a variety of informational displays in accordancewith exemplary embodiments of the invention.

FIG. 16 illustrates duct air measurements in accordance with exemplaryembodiments of the invention.

FIG. 17 illustrates air measurement and adjustment in accordance withexemplary embodiments of the invention.

FIG. 18 illustrates air measurement in accordance with exemplaryembodiments of the invention.

FIG. 19 illustrates air measurement in accordance with exemplaryembodiments of the invention.

FIG. 20 illustrates sensor modules and instrument interface modules inaccordance with exemplary embodiments of the invention.

It will be appreciated that elements in the figures are illustrated forsimplicity and clarity and have not necessarily been drawn to scale. Forexample, the dimensions of some of the elements in the figures may beexaggerated relative to other elements to help to improve understandingof illustrated embodiments of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The description of exemplary embodiments of the present inventionprovided below is merely exemplary and is intended for purposes ofillustration only; the following description is not intended to limitthe scope of the invention disclosed herein. Moreover, recitation ofmultiple embodiments having stated features is not intended to excludeother embodiments having additional features or other embodimentsincorporating different combinations of the stated features.

The apparatus, system, and methods of the present disclosure may be usedfor a variety of applications in HVAC, safety, lighting, and securitysystems in buildings and factories, including such applications as ductstatic pressure adjustment, airflow damper adjustment, room-to-roompressure adjustments, water side HVAC balancing, HVAC coil efficiencymeasurements, and the like. Included are measurements for immediate useas well as datalogging measurements at regular intervals over anextended period of time. As set forth in more detail below, theexemplary system and methods are generally easier to use, less timeconsuming, and require fewer and less expensive instruments compared totraditional systems and methods that provide similar functions.

FIG. 1 illustrates a system 100 in accordance with exemplary aspects ofthe invention. System 100 includes modules of various types formeasuring environmental parameters, and then viewing, storing, andsharing the measurement results. The modules of system 100 have wiredand/or wireless means of communicating information, commands, andmeasurement results. Illustrated system 100 includes control module 110,repeater module 112, sensor interface module 171, and a multitude ofsensor modules described below, one or more of which may optionally bepresent in system 100. Illustrated system 100 also includes means forenhancing the usability of control module 110, including wrist displaymodule 120, head-mounted display 121, audio module 122, thumbswitch 111,computer interface 131, PDA interface 134, and cellular data module 133.Use of system 100 improves user productivity in many ways, including: byallowing users to take measurements while using their hands for othertasks; allowing users to compare results from multiple locationsconcurrently; eliminating back-and-forth motion for repetitivemeasurements, facilitating information sharing among coworkers; easierset-up for complex and cumbersome measurements; facilitating moreaccurate results by maintaining measurement probes in-situ at thelocation of interest.

Users may include team leader 101 and associate 102. Users 101 and 102may have placed one or more sensor modules 150-156 and 161-165 inparticular locations to make specific measurements required forindustrial operations. Measurement results from sensor modules 150-156and 161-165 are transmitted to control module 110. Not part of thepresent invention are traditional instruments such as, e.g., watervolumetric flow meter 171. However, the present invention includesinterface module 172, which may connects to an existing data output portof flow meter 171, if present. Interface module 172 may transmitmeasurements wirelessly to control module 110.

Control module 110 establishes and maintains the network by which allsystem modules communicate. Control module 110 may also have otherfunctions, including display and storage of measurement data. Repeatermodule 112 has the function of a wireless signal repeater. This moduleis optional in system 100. When the distance between modules becomes toogreat for effective wireless transmission, repeater module may be placedmidway between the modules to allow signals to “hop”. Signals from thetransmitter are first received by repeater module 112, which in turntransmits over the now reduced distance to the receiver.

Control module 110 is operated via keys, buttons, and/or switches oncontrol module 110. Control module 110 may also execute certain commandswhich are entered by user 101 via buttons, keys, or switches onthumbswitch module 111. Control module 110 may also execute certaincommands which are entered by user 101 via microphone 123 on audiomodule 122. The ability to input commands verbally or via thumbmovements allows user 101 to use his hands for something else whilestill making and/or storing measurements.

Also important to productivity is the ability to see or hear resultswithout the need to use hands or arms. Control module 110 on user 101may transmit information, including measurement results, to wristdisplay module 120 on user 102, and/or heads-up display module 121,and/or audio earphones 124 on audio module 122. Time and effort aresaved by the ability of users 101 and 102 to both see the samemeasurement results at the same time despite their different locations.Other activities, including using hands for equipment repair and/oradjustment, may proceed while measurement results continue to arrive inreal time.

Voice communication between team members in different locations mayimprove productivity. Control module 110 on user 101 and display module120 on user 102 may include microphones and speakers and the softwareand hardware means to transmit voice via the same RF waves thatcommunicate measurement results. This may eliminate the need tocommunicate information or instructions by walking to conference, bywalkie-talkie instruments, or by cell phones. Headphone module 122 onuser 101, with microphone 123 and earphones 124, may also be used to forvoice communication, with transmission controlled by control module 110.

Productivity may be improved when information can be reviewed from agreat distance. For example, a manager at a home office may be able todetect an HVAC problem by viewing measurement results at a remotelocation in real time, and promptly give appropriate instructions.Building commissioners often share measurement information withcolleagues across the country to compare results from similar buildings.System of modules 100 provides means for transmission of information toremote servers 143, which may be accessed via the Internet. One way isfor the control module 110 to transmit to cellular data module 133,which in turn has a connection 141 through the cellular telephone systemto a remote server. A second way is for control module 110 to transmitto computer 130 via i/o module 131. Computer 130 may be directlyconnected to the Internet via a cable 141 or via a WiFi connection 142,both of which offer means of transmitting information from system ofmodules 100 to a remote server for world-wide viewing. A third way ofstoring information at one or more remote servers is via a PDA 135controlled by user 101. Data may be collected by PDA 135. Once stored inPDA 135, information may be transmitted to a remote server via WiFi orvia the cellular data network.

Module Components and Design Features

Exemplary electronic modules of the present invention include electronicassemblies built from customized printed circuit boards withmicroprocessor-based control circuits. The modules may be in relativelysmall enclosures of an appropriate size and shape for a specific systemfunction. Enclosures may be a standard product purchased from a suppliersuch as TEKO, or may be built to a custom design. Holes in theenclosures may be drilled to provide access for connectors, keypad,display, and mounting means such as a strap.

The contents of system 100 modules may include one or more of theseelectronic hardware and software feature sets:

embedded controller for general functions within a module.

LED's and/or other display devices and related display control.

Sensing electronics for analog or digital inputs.

Keypad and On/Off switch and other switches, keys, or buttons.

Battery and/or transformer.

Audio electronics, microphone, speaker(s), drivers.

Connectors for power, signals.

Wired signal transmission drivers and protocols.

Wireless transmission drivers and protocols, including RFpoint-to-point, RF multipoint, RF ZigBee, Bluetooth, WiFi, GPRS and/orother cellular data protocol.

Antenna(s) appropriate for the extant protocols and frequency channel.

System 100 may include a wireless sensor network (WSN). WSN's areestablished using standard hardware and software, included in every nodeof the network. For example, a ZigBit is a communications componentsupplied by Atmel with related software for installation in multiplemodules. The modules then have the capability to create and maintain aWSN based on the ZigBee Alliance protocol, which is an open standard.ZigBee uses an international standard 802.15.4 protocol and standard ISMfrequency ranges.

FIGS. 2( a) and 2(b) illustrate an exemplary wearable control module110. Loops 201 support a wrist strap 204 or a spring bracket formounting on other convenient apparatus. Control module 110 may also bemounted via magnets, Velcro, tape, or other means to an HVAC duct, pipe,rod, wire, cable, or other structure where convenient for the user.Keypad 202 may be used to control the display, storage of measurementresults in memory with time and date, and the network. Antenna 205 maybe a relatively long or relatively short dipole antenna that protrudesfrom the enclosure, or it may be another type of antenna installedinternal to the enclosure. Connectors 206 may be electrical ports forcommunication and/or power. Display 203 can show the results frommultiple sensors from multiple locations. A variety of display formatsare provided for specific applications, allowing the user to compare andcontrast different conditions in different locations. Real-time feedbackfrom adjustments of environmental controls is very beneficial toproductivity.

The present invention includes operating modes that were previously onlyavailable in different instruments. Control module 110 may operate in adiagnostic or debugging mode to discover and promptly fix problems.Control module 110 may also be used as a datalogger, collectingmeasurements regularly from multiple distributed sensors over a periodof hours, days, or weeks. The data may analyzed, for example by plottingthe information against time to show relationships between events.Control module 110 can operate in the debug mode or the datalogging modeor both at the same time. Two control modules 101 can operate at thesame time in the same network, one operating in debug mode and one indatalogging mode.

Multiple control modules 110 can operate in the same environment withdifferent sets of network modules. Unique addresses preventcommunication between the different networks.

Control Module Display Formats

Control module 110 includes the ability to display information in a widevariety of formats, depending on the desires of the user. Control module110 includes means for displaying and storing measurement results frommultiple sensor modules from multiple locations. FIG. 8 illustrates someof the formats available to users. Other display formats may beconfigured for specific measurement applications, as discussed below. InFIG. 8( a), large characters facilitate viewing from a distance. In FIG.8( b), a current reading is displayed in large characters at the upperleft, while smaller characters at the right list the three priorreadings. This gives an indication of the trend of the parameter. InFIG. 8( c), a current reading is displayed in large characters at theupper left. At the lower left are shown the current memory groupselected, AA, and the sequence number of the last value stored, 123. Onthe right are listed statistics for the current memory group AA,average, maximum, and minimum. In FIG. 8( d), results from two differenttemperature sensor modules, S1 and S2, are displayed side-by-side. InFIG. 8( e), results from two different sensor modules are displayedside-by-side. This type of sensor module supplies both a temperature anda relative humidity. The user can therefore compare four concurrentmeasurements from two different locations. In FIG. 8( f), concurrentresults are displayed from four different sensors in four differentlocations. Sensor module S1 is measuring temperature in ° F., S2 ismeasuring barometric pressure in inches of mercury, S3 is measuringpercent relative humidity, and S4 is measuring differential air pressurein inches of water column. In FIG. 8( g), a list of dataloggedmeasurements is shown with columns for record number, sensor number,time of record, value, and units. The date of the reading is displayedabove.

Control Module Construction

Control module 110 may have a keypad that is a membrane switch assemblyas illustrated in FIG. 2. Control module 110 may be powered by arechargeable lithium-Ion or lithium-polymer battery, which is rechargedthrough a mini-USB port.

Control module 110 may have an LCD display with LED backlight for goodvisibility in dark environments, embedded controller, memories,real-time clock, audio codec, speaker, microphone, connectors, keypad,and other electronic components. Control module 110 displays the resultswhich are received wirelessly at specified intervals from various sensormodules. Control module 110 may have a provision for storingmeasurements by pressing a key. Control module 110 manages the wirelessand or wired communications of system 100. The present inventionincludes programmed features to tailor the network to the environment offield users, who may not be trained in networking. Features included fornetwork durability and practicality in industrial environments includedisplays of status and problem alerts, and a “heartbeat” system in whicheach module regularly reports its status to control module 110.

Control module 110 may use an ATMega256 microcontroller by Atmel, butother similar microcontrollers, either 8-, 16-, or 32-bit, could havebeen chosen. Standard C programming techniques were used to produce thecontrolling program, using standard development software from, forexample, Atmel. The microcontroller of control module 110 performs thesefunctions:

-   manages power-on and power-off sequences-   monitors the keypad for user inputs, the real-time clock, and the    battery status-   feeds data and text to the display-   transfers data to and from the wireless network module-   manages the audio codec-   manages the mini-USB port for recharging the battery-   manages the mini-USB port for transmissions to and from a fixed or    mobile computer.-   manages the WiFi or other wireless port for transmissions to and    from a fixed or mobile computer.-   manages the wired or wireless port for transmissions to and from the    Web Access Module.-   manages the SD data port for storing data on a tiny SD-format memory    disk.

Alternate Embodiments

-   Control module 110 features may be implemented by a PDA or    smartphone or mobile computer to which is attached a network control    module.

Thumbswitch Module

FIGS. 3( a) and 3(b) illustrate thumbswitch 102, an optional module insystem 100, which can be worn on a finger via stretchable fabric loop301. If the user is holding tools or otherwise can't move his arm totouch the keypad 202 of wearable control module 110, he can effect asubset of keypress commands by pressing one or more buttons 302 on thethumbswitch as illustrated in FIG. 3( b). Examples of commands executedby wearable control module 110 but initiated via thumbswitch buttons 302include storing a reading and changing a display format. One or morestatus indicators 303 may be present. Thumbswitch 102 may fit indifferent places on different fingers, giving a user the flexibility tohold tools of different shapes while maintaining the ability to pressbuttons 302. Wearable thumbswitch 102, together with wearable controlmodule 110, and sensor modules that measure in-situ and need not beheld, allow users the freedom to perform tasks with their hands whilemeasuring and monitoring the environment.

Optional Modules for Disseminating Information

FIGS. 4( a), 4(b), and 4(c) illustrate head-mountable communication andcontrol apparatus. FIG. 4( a) illustrates some exemplary details ofhead-mountable display module 121 from FIG. 1. Small display 401 ispositioned in similar fashion to rear-view mirrors worn by bicyclists.Clamp 404 grips a cap, and supports small rod 403, from which display401 is suspended. Images may be provided by module 402, which may beoptionally attached to the back of a cap, attached to the back of acollar, placed in a breast pocket, or placed in some other location.Communication with control module 110 may be wired or wireless.

FIG. 4( b) illustrates exemplary details of audio module 122 fromFIG. 1. Headphone and microphone arrangement 411 provide audio contentsuch as measurement results and verbal messages from coworkers. Spokencommands may control control module 110. FIG. 4( c) illustratesexemplary detail of audio module 122 from FIG. 1. Common ear bud 422 mayuse Bluetooth protocol for communication with control module 110.

The electronics of head-mounted modules 121 and 122 may be batterypowered. Alternatively, the battery in control module 110 in FIG. 1 andFIG. 2 may feed the other components via a wire. Alternatively batteriesmay be integrated with the audio and/or video electronics modules, orexternal batteries may be located in a module worn on the user's belt,in his shirt pocket, clipped to the back of his shirt collar, or clippedto the back of his ball cap or helmet. Commands, measurement results,and information may be transmitted from module to module via wire or viawireless RF.

Optional Repeater Module

Remote sensor modules may communicate with a control module in a varietyof ways. Some of these are illustrated in FIGS. 5( a), 5(b), and 5(c).FIG. 5( a) illustrates a sensor module 511 in wireless communicationwith control module 110 from FIG. 1 and FIG. 2. The control modulemaintains a record of a unique identification number for sensor module511. Wireless communication parameters such as signal strength andfrequency are managed cooperatively by integrated hardware and software.Sensor module 511 makes regular measurements and transmits results tocontrol module 110. Control module 110 can display the results for theuser without storing them, or the user may cause the results to bestored with the value, units, sensor ID, time, and date. The user maycause the results to be stored without viewing them. The user may changethe schedule of measurement. When sensor module 511 is not measuring ortransmitting, it may put most of its electronic components into a sleepmode which uses very little power, such that a battery in sensor module511 may have a relatively long useful life.

As illustrated in FIG. 5( b), the user may require that sensor module511 be placed at such a distance from control module 110 that wirelesssignals are too weak to maintain effective communication. In thissituation control module 110 will display an alert to the user, who maythen deploy repeater module 521 at a location somewhere between sensormodule 511 and control module 110. Repeater module will be at aneffective distance to receive transmissions or information from sensormodule 511 and will retransmit said information, which control module110 is near enough to properly receive.

FIG. 5( c) illustrates that multiple repeater modules 521 and 522 may beused to extend the effective range between sensor module 511 and controlmodule 110. FIG. 5( c) also illustrates that control module 110 maymaintain communication with multiple sensor modules at the same time,included some that are in direct communication such as sensor modules512 and 513, as well as those whose messages are being repeated, such assensor module 511.

FIGS. 6( a) and 6(b) illustrate two exemplary configurations forrepeater modules. In FIG. 6( a), repeater module 601 includes an On/Offswitch 602 and one or more indicator lights 603. Repeater module 601includes a relatively small battery and a relatively small antenna, witha correspondingly short range, relatively speaking. In FIG. 6( b),repeater module 611 includes a large antenna 612 with a correspondinglylonger range, relatively speaking. A large battery is included, as wellas a transformer and wall electrical outlet prongs 613 for rechargingthe battery and/or operating while attached to mains power. A port 614is included for attaching a cable for information transfer and/orpowering from an external battery, solar panel, or other power source. Asensor 615 is included to allow repeater module 611 to measure andtransmit environmental conditions from its immediate area, in additionto performing its function as repeater. A display 616 is included so auser may view status and other information. Buttons and/or keys and/orswitches 617 are included to allow setup and manipulation of includedfunctions, in addition to On/Off switch 618 and indicators 619.

Sensor Modules—Common

Sensor modules are sensing instrument probes that measure environmentalparameters such as temperature, humidity, and pressure. The presentinvention includes many different types of sensor modules to address amultitude of HVAC applications. One or more sensor modules mayoptionally be present in an operating system 100. The present inventionoffers a common platform for users and reduces the number of differentinstruments required for HVAC applications, saving money and time.

FIG. 1 illustrates a multitude of sensor modules attached to variousHVAC fixtures where users may require measurements for solving problemsand/or adjusting equipment. For example, sensor modules 151, 152, and153 are placed in different locations of interest. Sensor module 151 hasa shaft type of sensing probe that penetrates a small hole in an airduct and measures temperature. Sensor module 152 has a button shape formeasuring the surface temperature of, e.g., water pipes. Sensor module153 measures temperature and humidity, and has a shape and features toallow users to easily attach it to, e.g., air supply ceiling diffusers.Sensor modules 151, 152, and 153, like other sensor modules in thepresent invention described below, may be designed to be relativelysmall and easy to place at a particular point of interest in HVACapplications. Sensor modules may be designed to remain at the point ofinterest, in-situ, and continue measuring and transmitting results to alocation convenient to the user. Sensor modules may have unique handlesand means of attachment to industrial equipment so they do not have tobe held by a technician when readings are being taken. When using sensormodules instead of traditional handheld meters, users need not makerepeated trips to a point of interest for follow-up measurements.

As illustrated in FIG. 1, sensor modules 551-556 and 561-565 may beplaced in or on air ducts, air diffusers, water pipes, condenser coils,walls, floors, ceilings, desktops, or many other places in buildings andfactories. It is the combination of size, shape, accessories (magnets,rings, clips, Velcro, adhesive dots, etc.), and the convenientcommunications link, usually wireless, to the Control Module 110, thatmake the sensor modules of the present invention uniquely suitable forindustrial measurement applications. When used in a system 100, sensormodules 151, 152, and 153, as well as other sensor modules describedbelow, reduce the time required for industrial procedures and improveaccuracy and safety.

The present invention may include wireless sensor modules for these HVACapplications:

-   Insertion air temperature.-   Surface temperature.-   Average temperature of ducts and mixing chambers.-   Insertion humidity probe.-   Fluid pressure and temperature in pipes.-   Differential Water Pressure Sensor Module-   Differential air pressure module with unique door mount.-   Velocity Sensor Module.-   Airflow probe for inlets and outlets.-   Other sensor modules for CO2 concentration, CO concentration, light    intensity, inclinometer, motor/fan rotor speed in RPM, switch status    (open/closed).

The present invention includes instrument interface modules 172 (inFIG. 1) which allow existing meters and sensors to be interfaced tocontrol module 110:

-   Instrument interface for instruments which have digital output    ports, such as these instruments popular in HVAC applications:    Shortridge AirData Multimeter™ series; TSI/Alnor EBT 720 series;    Kanomax Climomaster A5xx series; other instruments with digital    outputs.-   Instrument interface for third-party instruments and sensors which    feature standard analog outputs formats: 4-20 mA; 0-to-5 volts;    0-to-10 volts.

Sensor Module Construction

Sensor modules, including sensor modules 551-556 and 561-565, mayinclude: a custom printed circuit board, one or more status LED's,sensor or sensor connector, battery, communication circuitry. One ormore microcontrollers are programmed to control the LED indicator(s),power on and power-off sequences, battery power monitoring, and sensorinterface. Sensor modules may use primary or rechargeable batteries, andmay also provide means for mains power and/or external battery power.Sensor modules include means for attaching to key locations of interestand remain in-situ while delivering a stream of regular measurements.

Temperature Sensor Module

FIG. 9 illustrates a temperature sensor module 901, including a sensingand radio electronics part 902 and a connected sensing probe 911 or 912or 913. Sensor probe 911 has a sensing element 921 at the end of a stiffshaft. Sensor probe 912 has a flexible lead attached to a button-stylesensing bulb 922. Sensor probe 913, for applications that require theaverage temperature in a space, has a thermally-conductive lead in whichare located one or more temperature sensor elements 923. Each of sensors911, 912, and 913 may be connected to sensor module 901. Sensor module901 includes an On/Off switch and one or more LED's or displays. Sensormodule 901 includes magnets 931 and 932 applied to two facets of themodule for attaching to ferrous surfaces. Facet 933 has a surfaceappropriate for taping sensor module 901 to a non-ferrous surface. Ring934 allows clipping or hanging from lines or pipes or other availablestructure.

FIG. 7 illustrates some applications of temperature sensor module 901.Illustrated is a simplified model of an HVAC system serving part of abuilding. Sensor module 901 with sensor probe 911 sits on a table tomeasure room temperature. Sensor module 901 with sensor probe 911 usesmagnet 931 to attach to ferrous fixtures at ceiling locations 702 and703. Location 702 represents supply air temperature entering room 708,while location 703 measures the temperature of room air as it passesthrough a return air grille and enters a return air duct. A sensor oftype 901 is located at 719 to measure return air temperature and anotherat location 710 measures fresh outside air being brought in to ventilatethe building and replace stale air. In mixed air chamber 713, two airstreams collide in a turbulent environment, where temperature probe 913,is used to measure the average air temperature. The mixed air exitsthrough filter 714. Fan 715 propels the air past coil 716 and into thesupply air duct. The temperature of the water in the coil pipe isapproximated by the sensing probe 922, which is held against the pipewith tape or strap. Ring 934 provides means to hang the sensor module901 near the location to be measured.

Method for Measuring Mixed Air Proportions

FIG. 7 also illustrates the present invention resulting in an improvedmethod. HVAC industry rules require a certain amount of fresh outsideair for each square foot of occupied space. An air balancer must supplyjust enough, but not too much, outside air. Dampers 711 and 712, alongwith fan speeds, are varied to achieve the necessary outside air. Airbalancers make a calculation to determine outside air volume bycomparing the respective temperatures of supply air, return air, outsideair, and mixed air. Industry practice is to measure each location (709,710, 713, 706), then adjust the dampers, then measure again, repeatingthis cycle until the required relationships of temperatures areachieved. This is an iterative process that is time consuming. Thecurrent invention allows sensors to be placed as described above.Control module 110 provides four continuous readings from four differentlocations in the format shown in FIG. 7( b): return air temperature 721,outside air temperature 722, mixed air temperature 723, and supply airtemperature 724 (after being cooled by coil 716). With this improvedmethod, the required adjustments can be made relatively quickly,reducing manpower and shortening schedules.

In accordance with additional embodiments of the invention, a method ofmeasuring mixed air proportions includes the steps of:

deploy averaging temperature module 913 in the air mixing chamber;

deploy insertion temperature module 901 in the outside air duct;

deploy insertion temperature module 901 in the return air duct;

deploy insertion temperature module 901 in the supply air duct;

display results from four sensor modules concurrently on control module110;

calculate the proportion of supply air that is outside air;

calculate the outside air volume;

calculate the desired outside air volume based on occupancy, usage type,etc.;

compare the desired outside air volume to the desired outside airvolume;

adjust outside air damper and return air damper while observing thechanges in measured air temperature on control module 110.

Traditional methods require many iterations of measurements, accompaniedby a lot of back and forth movement. The ability to deploy sensormodules for continuous measurements saves a lot of time and effort.Also, because it is relatively easy to achieve a precise outcome, usersare less likely to take shortcuts which may retain an undesirable levelof outside air.

Humidity Sensor Module

FIG. 10 illustrates exemplary configurations of humidity modules thatare part of system 100. Sensor module 1001 includes sensing probe 1002,which can be used with or without extension rod 1003. The longerconfiguration is useful for placing the sensing element 1004 at aparticular location in large ducts. Sensor module 1001 with sensingelement 1004 measures temperature as well as humidity. FIG. 10( c)illustrates four different exemplary results available from onemeasurement: relative humidity percent 1011; dry bulb temperature 1012;wet bulb temperature 1013; dew point temperature 1014. Optional resultsnot shown include grains of water per cubic foot. FIG. 10( d)illustrates exemplary displays from two humidity modules in differentlocations. A user may view for comparison these results: RH from S-11021; dry bulb temperature from S-1 1022; RH from S-2 1031; dry bulbtemperature from S-2 1032.

Differential Air Pressure Sensor Module

FIG. 11 illustrates an exemplary of a differential air pressure sensormodule. FIG. 11( a) illustrates a version of the sensor module with twoports, and FIG. 11( b) illustrates a four-port version. The pressurebetween the ports is measured and transmitted to control module 110.

Air pressures are involved in a multitude of HVAC applications,including duct static pressure and velocity pressure. Duct staticpressure is the difference between the pressure of duct air and roomair. Velocity pressure is related to air velocity. It is measured as thedifference between two types of orifices on the probe. FIG. 11( c)illustrates both of these measurements.

FIG. 11( c) illustrates differential pressure sensor module 1101attached via included magnet 1113 to the side of an air duct. Anindustry standard probe 1132, a static tip, is inserted through a holein the wall of duct 1131 and oriented into the airstream such that thestatic pressure of the duct is present at probe output port 1134. Aflexible hose is connected between port 1134 and sensor module port1111. The sensor module then measures the difference between thepressure of the air in the duct and the pressure of the air outside theduct. The result, e.g., 1.25 inches of water column, is sent wirelesslyto control module 110.

Also in FIG. 11( c), differential pressure sensor module 1102, with fourports, is attached via included magnets to the side of air duct 1131. Anindustry standard probe 1141, a Pitot tube, is inserted through a holein the wall of duct 1131 and oriented into the airstream. Pitot tube1141 has two output ports, and there are two differential pressurestypically of interest to users. Connected to the static pressure port isflexible hose 1142, which is connected to sensor module 1102 ports 1121and 1123. Another flexible hose 1143 is connected to sensor module 1102port 1124. In this configuration, the sensor module transmits tworesults of interest to control module 110. Duct static pressure is thedifference between sensor module ports 1121 and 1122. Velocity pressureis the difference between sensor module ports 1123 and 1124.

Differential pressure module s 1101 and 1102 are useful in severalapplications, including setting duct pressure, setting room-to-roompressure, setting occupied space pressure vs. outside air, fume hoods,biosafety cabinets, and others. Most commercial and industrial buildingsare specified to have a slightly positive pressure to prevent ingress ofoutside air, humidity, leaves, and bugs (think restaurant dining areas).The pressure drop across filters is a key measure of the cleanliness offilters. The present invention is designed to quickly and easily detectproblems in these areas and alert a technician, building manager, orrestaurant owner. The present invention provides results of pressuremeasurements from multiple locations to be reviewed and comparedconcurrently, which reduces the time involved in certain procedures. Anexemplary application is described below.

Application: Measuring and Adjusting Room-to-Room Differential Pressures

The innovative capabilities of the present invention are especiallyimportant for cleanroom applications such as semiconductors,pharmaceutical, and hospitals, where multiple related pressures arespecified. FIG. 13 illustrates a wafer fabrication facility 1301 withoutside walls 1302, an exterior entry 1303, corridor 1304, suit-up room1305, air wash 1306, general operations area 1307, and mini-environmentfor special processes 1308. The requirement for air cleanliness dependson the nature of the area. Pressure differences are one of the primarymethods of controlling the direction and degree of contaminant movement.That is, a space with a great need for cleanliness will be specified tohave a higher pressure than adjacent areas. Typical room-to-roompressure differences are maintained between 0.03 inches of water columnand 0.06 inches of water column. For the building illustrated in FIG.13, there may be a specification for these pressure differences:

R1304 to 1303: 0.02 in. wc.

R1305 to 1304: 0.03 in. wc.

R1306 to 1305: 0.04 in. wc.

R1307 to 1306: 0.05 in. wc.

R1308 to 1307: 0.05 in. wc.

Pressure differences are created by adjusting fan speeds and dampers toadjust the volume of supply air and return air for each space. The fansand dampers may be located at quite some distance from the points beingmeasured. The pressures are interrelated, so adjusting one fan or dampercan affect two or more room-to-room pressures. A conventionaldifferential pressure sensor, usually held near a door by a technicianusing two hands, can measure only one or two differential pressures at atime, and the result is nowhere near the point of control, the fan ordamper. The user records the measurement, moves to the point of control,makes and adjustment, and returns to make another measurement. The HVACsystem is often organized such that the room characteristics areinterrelated. An adjustment of one fan may affect two or three rooms,causing rooms that were in spec to go out of spec. Then the processbegins again. The current industry method involves a long, drawn-outseries of measurements and adjustments.

The present invention allows multiple sensors to be placed wherenecessary. The room-to-room pressure measurements are continuouslytransmitted wirelessly to the wrist of the technician, who can displayand store two or more measurements at the same time. In most cleanroomsbuildings the technician has access to the control elements from aninterstitial level above the cleanrooms themselves. With the informationprovided by the present invention, he can quickly achieve all of thespecified pressure setpoints, saving a lot of time and effort.

Method of Measuring Room-to-Room Pressures

In accordance with additional embodiments of the invention, a method ofmeasuring a multitude of room-to-room differential pressuresconcurrently includes the steps of:

deploy differential pressure sensor modules to each location ofinterest;

line each sensor module with the control module;

deploy repeater module(s) if necessary for increased range;

select an appropriate display format on control module;

observe differential pressure measurements in real time from a multitudeof locations.

Current methodologies are of two types. One way is for one person tomove sequentially to each location of interest, measuring and recordingresults, and often returning to repeat measurements to note changes.Another method is to deploy multiple operators, each with an expensivehandheld instrument, who communicate by shouting, moving forconferences, via walkie-talkies, or via cell phones. The exemplaryembodiment of the present invention clearly offers a dramaticimprovement in productivity for this type of application through the useof distributed sensor modules that are relatively inexpensive, togetherwith novel formats for measurement presentation that allow quickfeedback on control changes and component interactions within HVACsystems.

Method for Setting Duct Static Pressure

In HVAC duct systems it is important to maintain a minimum level ofpressure at the extreme end of the duct system in order to maintainairflow through the duct and diffusers. For instance, a buildingengineer might specify that the fan generate a duct pressure that is 3inches of water column above the ambient pressure in the building(static pressure), and that the system of valves and dampers be adjustedsuch that the most remote air diffuser will be supplied air at apressure of at least 0.5 inches of water column. It is critical that thepressure at this point be carefully controlled. If too low, thediffusers will not distribute conditioned air as designed and buildingcomfort will suffer. If too high, energy is wasted by running the fantoo fast. If the technician measures only 0.4 inches of static pressure,he needs to adjust the fan and/or the dampers to increase the remoteduct pressure to the minimum of 0.5 specified. However, if the pressureis higher than required, the excess fan power will use far moreelectricity than it should. The electric power required increases at thecube of the duct pressure increase. For instance, if the fan speed isincreased to raise the remote duct pressure to 0.55 inches, only 10%higher than required, the fan will use 30% more electric power thanrequired. (The calculation has the form of 1.1×1.1×1.1=1.3.) Currentprocedure requires a technician to measure the pressure at theappropriate point in the duct, and then move through the building toadjust the fan and the dampers. He then returns to measure pressureagain. This cycle of measurement and adjustment will be repeated untilthe specified result is achieved. Sometimes the fan is a long distancefrom the point being measured, and on a different floor. This repetitiveprocedure requires a lot of time and effort, and leads to the techniciansettling for some safe guard-banded pressure instead of achieving theprecise result desired. This is one of the main sources of wasted energyin buildings. What the technician needs for applications like this is astream of real-time measurements taken at the point of interest anddelivered to him where and when he is making the adjustment at the pointof control.

Method

In accordance with additional embodiments of the invention, a method ofmeasuring a multitude of room-to-room differential pressuresconcurrently includes the steps of:

deploy differential pressure sensor modules to the points of interest,which may include not just the end point of a duct, but several pointsthroughout the duct system which may be affected by a control change;

link each sensor module to the control module;

deploy repeater modules if necessary for range;

select a useful display format;

observe existing status of duct system pressures;

effect changes in fan speed or damper settings;

observe static pressure responses to control changes in real time frommultiple locations.

Pipe Fluid Pressures and Temperatures

The present invention includes means to measure temperature and pressureof fluids in pipes. FIG. 12 illustrates the use of sensor modules in anexemplary application. Fluid 1200, e.g., water, moves through pipe 1210.Pipe 1210 includes three fixtures known as PT test points (pressure andtemperature), which are sometimes implemented using a water-tight accessport called a Pete's Plug (1213 in FIG. 12). If temperature alone isdesired, sensor module 901 from FIG. 9, or a similar sensor module, maybe inserted through a Pete's Plug as illustrated at location 1211.Temperature measurements will be transmitted continuously to controlmodule 110.

If pressure is desired as well as temperature, sensor module 1221 may beinserted through a Pete's plug as illustrated at location 1214. Sensormodule 1221 allows pressure and temperature measurements to be madeconcurrently from the same Pete's Plug. The current invention includesmeans, via sensor module 1221, to transmit static pressure andtemperature concurrently.

Valve 1212 may be adjusted to control the flow of fluid, and a user maydesire to know the volumetric fluid flow. Valve 1212 may be calibratedso if the pressure drop across the valve is known, the volumetric flow,e.g., in gallons per minute, can be determined from a chart or equation.Sensor module 1221 can measure the differential pressure betweenlocations 1214 and 1215 as well as the static pressures at each pointand the temperature of the fluid. All results are transmitted to controlmodule 110. It is often desirable to have these results availableconcurrently. It is also often desirable to have these results availablefrom multiple locations concurrently.

Method

In accordance with additional embodiments of the invention, a method ofmeasuring pressure and/or temperatures at a multitude of points in apipe system concurrently includes the steps of:

deploy pressure and temperature sensor modules to each point ofinterest;

if desired, deploy water flow meter with connected instrument interfacemodule;

link each sensor and interface module to the control module;

deploy repeater modules if necessary for range;

select a useful display format;

observe existing status of system pressures and temperatures;

effect changes in pump speed or valve settings;

observe multiple responses to control changes in real time from multiplelocations in a user-friendly display format.

Velocity Sensor Module and Probe Apparatus

Air velocity is frequently required in HVAC. The present inventionincludes a velocity sensor module with unique features. A velocitysensor module, in coordination with temperature and/or humidity modulesand a control module, form a system of distributed sensors that allows auser to make velocity and pressure measurements in air ducts morerapidly, more conveniently, more accurately, and more safely. Thepresent invention may also be used to measure air velocity and pressurein applications other than ducts. The present invention uses a methodbased on differential air pressure, which is applicable to traditionalvelocity probes such as Pitot tubes.

A widely used formula for air velocity is derived from fundamental lawsof physics:

V=1096.7×square root of (VP/d), where:

-   V is velocity in feet per minute-   VP is velocity pressure in inches of water column

d is density of air in pounds per cubic foot=1.325×BP/T, where

-   BP is barometric pressure in inches of mercury

T is absolute temperature=degrees Fahrenheit+460

The present invention includes sensors and valves for making accuratemeasurements of T, BP, and VP of duct air. FIG. 14 illustrates a system1403 for making measurements in an air duct. Often these measurementsare part of a standard procedure, a velocity traverse of a duct. Thisprocedure determines the conditions at a cross-sectional plane of aduct. Air conditions include barometric pressure, temperature andoptionally humidity. Air conditions also include static pressure at oneor more points on the cross-section. Conditions also include the insidedimensions of the duct, free of any insulation that may coat the ductwalls. From these dimensions, a user consults standard tables and/orformulas to determine the matrix of points in the duct cross-section atwhich velocity must be measured. Air velocity is not uniform in thecross-sectional plane, so many measurements must be performed atdifferent locations and the results averaged. The average velocity timesthe cross-sectional area equals the airflow volume at that point in theduct system.

FIG. 14 illustrates a duct traverse procedure using an exemplaryembodiment of the present invention. Air or another gas flows throughduct 1401 with duct walls 1402. Air velocity is not uniform across theduct as illustrated by velocity vectors 1403. The user must determine anaverage velocity in the duct by making and storing many measurements atspecific locations 1404 located in the cross-sectional plane of the duct1401. A user holds Pitot tube 1405 steady at each location 1404, andmakes and stores a velocity reading. Then the user moves the Pitot tubeto the next location for another measurement. Industry standardprocedures may require measurements at 16 or more, sometimes as many as200, separate locations in the duct.

A Pitot tube 1405 has an orifice 1406 at the tip which when facing intothe airstream develops total pressure. A Pitot tube has at least oneother orifice 1407 that develops static pressure if not directlyimpacted by the passing airstream. A Pitot tube includes separatechannels to conduct the two pressures outside the duct where they may beconnected by hoses to velocity sensing module 1410. One hose connectsthe static pressure port 1409 of Pitot tube 1405 to the static pressureport 1411 on velocity sensing module 1410. Another hose connects totalpressure port 1408 on Pitot tube 1405 to total pressure port 1412 onvelocity sensing module 1410.

Velocity sensing module 1410 includes valves, sensors, microprocessors,and other components to accurately measure total pressure, velocitypressure, and static pressure concurrently. The measured values aretransmitted to control module 1430. Sensor module 1420 is insertedthrough a hole in duct wall 1402 and remains in-situ measuringtemperature and/or humidity. The measured values are transmitted tocontrol module 1430, which calculates and displays all of the results ofinterest to the user. Control module 1430 may be worn on the user'swrist, or mounted to the duct wall 1402, or otherwise placedconveniently. The user may store measurements by reaching to press thekeypad of control module 1430. Alternatively, the user may store resultsand perform other control functions by pressing buttons on thumbswitch1431. Stored results are “stamped” with the associated time and date.The user may choose from a variety of display formats, which areillustrated in FIG. 15. The present invention includes means forproviding key information of different types to the operatorconcurrently to save set-up and measurement time and to improveunderstanding of the environment. Key among those innovative informationdisplays are the concurrent measurements of velocity and staticpressure.

FIG. 16 illustrates some improvements provided by the present inventionover traditional methods. User 1601 holds a traditional velocity meterin one hand and manipulates the keypad with his thumb. Tubes 1611 and1612 loop down from Pitot tube 1405. Tube 1611 has gotten caught onladder. When the tubes 1611 and 1612 dangle and swing, measurementresult may be less accurate. Temperature sensor 1613 is inserted throughduct wall 1402 and connected to meter 1610 with a coiled cable. User1601 stands on a ladder with his head in a dark area above the ceilingtiles 1614. User 1601 moves his head up and down alternately, first upto position Pitot tube 1405 for a measurement at a proper matrix point,then down to view and store the results on the meter. FIG. 16illustrates the cumbersome nature of the velocity traverse procedure. Itis not uncommon for users to simplify the process by skipping thetemperature measurement, which affects accuracy.

When user 1601 finishes the velocity traverse matrix, he lacks anecessary measurement, static pressure. User 1601 withdraws Pitot tube1405 and temperature sensor 1613 from the duct. User 1601 removes thetemperature sensor. User 1601 disconnects tubes 1611 and 1612 from themeter. User 1601 replaces tube 1611 on the meter at a different port.User 1601 presses keys to change the meter mode from velocity topressure. User 1601 reinserts Pitot tube 1605 into the duct and orientsit into the airstream. User 1601 presses the meter to read and recordthe static pressure in the duct.

User 1402 in FIG. 16 uses system 1403 of the present invention. Velocitysensor 1410 is attached to Pitot tube 1405 with stiff tubing that doesnot move during a measurement. The display of control module 1430 andthe position of Pitot tube 1405 are both visible to user 1402 withoutmoving his head. No tubes dangle from Pitot tube 1405. No coiled cableis attached to temperature sensor 1420 to present an obstacle. User 1602has one arm and hand free to grasp a nearby fixture 1603 for improvedsafety. Free of cumbersome tubes and cables, and provided more visibleresults, his motions are faster and more precise. When user 1602finishes traversing the matrix, he may view all of the measurementresults as illustrated by FIG. 15. No setup changes are necessary toobtain static pressure. Static pressure was measured concurrently withvelocity and temperature. A special interactive display mode of theControl Module facilitates the measurement and provides a convenientdisplay of the results. An element of the present invention is theability to display related measurements simultaneously when thetechnician usually requires the knowledge. An example in this case isDuct Static Pressure. FIG. 15 illustrates an exemplary embodiment of acomplete display of desired information.

Method of Measuring Duct Static Pressure

In accordance with additional embodiments of the invention, a method ofconcurrently measuring temperature, velocity, and static pressure in anair duct includes the steps of:

deploy insertion temperature sensor module to a suitable duct location;

connect two pressure ports of a velocity sensor module to the static andtotal pressure ports of a Pitot tube or similar probe;

link control module to temperature sensor and velocity pressure sensor;

place Pitot tube inside an air duct at point of interest;

multiple measurements of multiple types are received from multiplelocations and displayed on control module for storage and/ordissemination and/or uploading to computer or Internet.

The present invention is used with industry-standard Pitot tubes, whichare available for purchase from Dwyer, Cole-Parmer, and other HVACindustrial supply companies. Pitot tubes vary in length from a fewinches to five feet or more.

The Velocity Sensor Module will also support Static Pressure measurementwith industry standard static pressure probes. The present inventionwill support many other forms of velocity and pressure probes.

Alternate Embodiments of Velocity Sensor Module

Sensor module 1410 may be firmly attached to Pitot tube 1405. Sensormodule 1410 may have an enclosure that envelops part of Pitot tube 1405.Said enclosure may have a part that is shaped like a bicycle handle gripto enhance usability.

Air density is strongly affected by barometric pressure and temperature.Sensors for those two parameters are therefore necessary parts of anaccurate velocity sensing system. The effect of humidity is lesspronounced, so humidity sensors are not typically used in velocitymeasurement systems. The distributed and wireless nature of the presentinvention makes it easier for the user to utilize a humidity sensor andtherefore achieve a higher than normal accuracy.

Airflow Sensor Module and Capture Hood Apparatus Airflow Sensor Module

The present invention includes an airflow sensor module which is usedwith existing airflow capture hoods. FIG. 17 illustrates a dampersetting procedure performed in two ways. Two rectangular ceilingdiffusers 1710 are to have their airflow volume adjusted to meet thespecification. Users 1 and 2 use a traditional capture hood andtraditional method. User 1 holds a heavy, awkward capture hood tightagainst the ceiling fixture to try to capture all of the airflow, whichflows across velocity grid 1723. Velocity grid 1723 works on adifferential pressure principle similar to that of a Pitot tube. Whenairstream 1712 flows across velocity grid 1723, a pressure difference isgenerated between an upstream pressure in tube 1721 and a downsteampressure in tube 1722. These tubes are connected to positive andnegative pressure ports on meter 1730. Meter 1730 measures thedifferential pressure and calculates a velocity. The meter thenmultiplies the calculated velocity by the cross-sectional area ofcapture hood 1720, and displays a volumetric airflow, e.g., 220 cubicfeet per minute (CFM). User 1 sees the result and shouts it to histeammate user 2. User 2 is on a ladder to reach and adjust the damperthat controls flow to ceiling diffuser 1710. After making an adjustment,user 2 waits for user 1 to shout a changed result. This iterativeprocess repeats until the specified airflow is reached.

User 3 uses airflow sensor 1740 of the present invention. Airflow sensor1740 performs the same measurement and calculation functions as meter30, and transmits continuous results to control module 1742 on the wristof user 3. As user 3 adjusts the damper, he sees the changed result inreal time.

The weight of airflow sensor module 1740 is a small fraction of theweight of meter 1730, because it is designed for a distributed sensingsystem, and needs no display, keypad, or other features that burdenmeter 1730. It is much easier to lift and place capture hood 1720 withairflow sensor module 1740 installed than for the same capture hood withmeter 1730. This can be done by a human operator, or it can be done by ajack or stand 1750, which allows one person to perform a damper settingfunction. A jack or stand 1750 could also be used with meter 1730, butuser 2 would have to climb down the ladder once in a while to read thedisplayed result.

FIG. 17 illustrates another long-standing problem with traditionalmethods and illustrates a corresponding advantage of a distributedsensing system. As with Pitot tubes, airflow sensors must include airdensity in the calculation. However, temperature sensor 1731 istypically poorly designed and poorly positioned to contribute anaccurate figure. It takes too long, e.g. up to three minutes, forairstream 1712 to heat or cool temperature sensor 1731 to the correcttemperature. Most users cannot wait that long so they forego thetemperature component and accept an inaccurate result. User 3 hasinstalled a fast-acting temperature sensor on a support strut 1724 ofcapture hood 1720. It measurement of temperature is transmitted tocontrol module 1742 and is included in the airflow calculation. Optionaltemperature features included with control module 1742 are to lock in aparticular temperature measurement for use with all subsequentmeasurements, or to manually enter a known air temperature for use insubsequent airflow calculations.

Airflow sensor 1740 is far less expensive than meter 1730, allowing morewidespread use.

FIG. 18 illustrates other unique benefits of the present invention. Aroom has three supply air diffusers and one return air diffuser. Jacksor stands 1750 hold four capture hoods in place. One operator 3 can viewthe airflow figures for all four diffusers at the same time. He canadjust the dampers of one after another without moving the capturehoods. Airflow volumes of diffusers on the same system are ofteninterrelated. Adjusting one damper can cause changes of all fourairflows, not just the one an operator is seeking to adjust. Withtraditional equipment and methods, many iterative measurements arerequired before each diffuser achieves the specified airflow. With thepresent invention, the interrelationships are revealed to the operatorand corresponding adjustments can be made quickly, saving a lot of time.The ability to view multiple results concurrently offers and unexpectedbenefit for operators.

Airflow Capture Hood

The present invention includes a relatively small, light-weight capturehood for measuring airflow at inlets and outlets. Traditional capturehoods such as capture hood 1720 with meter 1730 in FIG. 17 weigh about 9or 10 pounds. Replacing a traditional meter with airflow sensor module1740 reduces the weight to about 7 pounds. The present inventionincludes a capture hood that weighs about 3 pounds. It is constructedwith the same type of aluminum, carbon fiber, and modern fabrics thatare used in the construction of tents and clothing for mountainclimbing. The capture hood of the present invention is not constrainedby the need for a mounting platform for a heavy meter. FIG. 19illustrates the design and functions of the present invention, capturehood 1901. The frame may be light and relatively flexible compared totraditional capture hoods. There may be two or more optional locationsfor the airflow sensor 1740, on the side or beneath the velocity grid.Quick-responding temperature sensor or temperature and humidity sensor1741 is attached to the upper frame where it will have early contactwith the airstream. Three or more means are provided for attaching thecapture hood to the diffuser such that the operator can move away foradjustments or other measurements. These new methods are not practicalfor heavy capture hoods, but are practical for a hood weighing onlythree pounds. Spring hook 1943 hooks over a vane of diffuser 1710, andtension holds the light capture hood tightly against the diffuser.Alternatively, magnets 1944 around the perimeter of the capture hoodattract to the ferrous strip around the ceiling diffuser. Alternatively,spring clamps may hold capture hood 1901 tightly against the ceilingstrips between tiles. Alternatively, a thin, lightweight extensible rod1945 may be placed between the floor and the capture hood, pinning itagainst the ceiling diffuser.

Proportional Balancing

Proportional Balancing of HVAC Duct Systems was discussed above. Thereis often a need to observe and understand how the adjustment of onediffuser damper is affecting the airflow at the other diffusers in thesame duct system. This can be done by propping up a capture hood at adiffuser and wirelessly monitoring it while adjusting other dampers.

Another way to monitor the change is to use a Pitot tube. It is ofteneasier using magnets and grippers to position a Pitot tube in the ductleading to the diffuser in question than it is to jack up a capture hoodagainst the ceiling diffuser. The Pitot tube can then wirelesslytransmit a percentage change in measured velocity at a point in the ductcross-section that represents the total airflow. The important parameteris the percentage change caused by the damper adjustment, not the amountof airflow itself.

The Velocity Sensor Module of the present invention will make furtherimprovements in the time and accuracy of Proportional Balancing. Usingmagnets or other holding means, a Pitot tube can be temporarily fixed inplace at the center line of the duct feeding the furthest duct, thereference duct, as mentioned above. The air velocity measured at thatpoint can be correlated to the airflow measured through the diffuser.When an adjustment shows that an upstream duct adjustment caused aparticular change in the duct velocity, such as 5%, it can be assumedthat the airflow also changed by 5%, and an airflow measurement can beavoided. The final airflow can be measured at the diffuser as usual toverify the result, but the intermediate measurements can be avoided andmuch time saved.

Method

In accordance with additional embodiments of the invention, a method ofmeasuring at multitude of locations concurrently includes the steps of:

deploy sensor modules to the points of interest, including airflowsensor modules on capture hoods, and/or velocity sensor modules on Pitottubes or similar probes, air pressure sensors attached to duct staticpressure sensing probes, and/or room-to-room pressure sensor modules,and/or other related sensor modules;

link each sensor module to the control module;

deploy repeater modules if necessary for range;

select a useful display format;

observe existing status of duct system at a multitude of locations;

effect changes in fan speed or damper settings or other changes;

observe duct system response in real time from multiple locations.

Other Sensor Modules

The present invention includes other sensor modules that measure lightintensity, radiation, CO2 concentration, CO concentration, motor/fanrotor speed in RPM, degree of incline (for dampers and grille degree ofopenness), pulse counters (for electric meters and other types), andswitches (for doors open/closed and machines on/off). Other sensormodules are constructed in a fashion similar to the temperature sensorsof FIG. 9. Other sensor modules are illustrated in FIG. 20. In FIG. 20(a), the sensor module 2001 may have a sensing element as an integralpart of the module. Alternatively, the sensor module may have thesensing element 2020 located in a shaft-type of probe as in FIG. 20( b).Alternatively, as illustrated in FIG. 20( c), other sensor module mayhave a sensing element 2030 located at the end of a flexible cable.

Instrument Interface Module

The present invention also makes existing instruments more useful inseveral ways. First, the result is sent wirelessly to where it isneeded. Second, the control module display and viewing angle willusually be superior. Third, the control module provides a very largememory for storing measurements and provides beneficial statistics thatare often missing in other instruments. Fourth, the Thumbswitch allowshands-free storage of measurements. Fifth, the measurement data can beshared by multiple technicians in real time.

Digital Outputs

For instance, this type of Sensor Module can utilize the digital resultsfrom existing instruments such as the AirData Multimeter from ShortridgeInstruments. This allows the benefits of the present invention to beapplied to the use of the third-party meter. Results can be sentwirelessly to a remote location, the user can view the results on hiswrist while his hands are free for another operation, a large memory isavailable for storing data, and the Thumbswitch allows him to store datawithout moving his arm. The Interface Module is adaptable to match theelectrical and mechanical output of the third-party meter. The ADM-870Cmeter from Shortridge Instruments provides an RS-232C serial data outputthrough a standard round connector.

Interface Module for Analog Outputs

Ultrasonic fluid flowmeters and other existing instruments, sensors, andtransmitter have analog outputs such as 0-5 volt, 0-10 volt, and 4-20 mAcurrent loop. This Module uses the same basic foundation as the DigitalInterface Module, but includes circuitry to convert the analogmeasurement to a digital value for wireless transmission.

Pulse counters.

Open/close switches.

Instrument interface modules may have characteristics illustrated inFIG. 20( c). Connector 2030 is designed specifically for the output ofthe instrument of interest. It is attached to the end of a flexiblecable 2031 which carry signals to conversion and wireless circuitryinside module enclosure 2003.

Operation in Exemplary Applications

The modules (control, sensor, and, if present, thumbswitch, repeater,and other types) are collected and turned on. They automatically join awireless network and the control module displays a Link Status showingall of the modules in the network. The technician deploys each sensormodule as appropriate to the function he is performing, such astemperature, humidity, pressure, etc. The technician straps the controlModule to his wrist or otherwise positions it for easy viewing. Atspecific intervals, the measurements made by the sensor modules areradioed to the control module and displayed. The technician may storethe measurements in memory if desired, either by pressing a key on thecontrol module's keypad or by pressing a key on the thumbswitch.

The invention addresses the key deficiencies of other HVAC instrumentsas noted above. Measurements can be taken at the point of interest andresults delivered to the technician for immediate action as necessary.What is delivered is a stream of real-time data, not one or twooccasional measurements that represent a particular point in time. Thetechnician's hands are free to make the physical changes necessary, suchas repairs or adjustments. A team of technicians can wear modules andshare the results in real time for improved team productivity. Further,an integrated walkie-talkie is available for team coordination.

The invention allows the technician to install a remote sensor, thenmove around the building to make the necessary adjustments while astream of real-time measurements are radioed to him. Thus informed, thetechnician can make exactly the right adjustments to achieve a preciseresult. This saves a lot of time and gives a much better result.

The invention offers another advantage in that it can make existinginstruments far more useful and productive. This is a uniqueness factor.An example is the AirData Multimeter from Shortridge. These instrumentsmeasure air pressure, temperature, velocity, and flow. Model 870C ofthis series of instruments has a serial output that can feed a stream ofdata to a wireless module which is a component in the invention. Thedata is then distributed wirelessly to the wrists of the technician teammembers, who can quickly make the necessary HVAC adjustments. Followingis one example of the power of this improvement. Current practice is forone person to hold up a capture hood to an air outlet in the ceilingwhile another person climbs a ladder, removes a ceiling tile, andlocates the damper that controls the air flow to that diffuser. Themeter on the capture hood displays the amount of air coming through thediffuser into the room in cubic feet per minute. The person holding upthe heavy capture hood, with some difficulty because of the sight anglesinvolved, then reads the meter's display and shouts it to his partner,who adjusts the damper accordingly, trying to achieve a specifiedresult. Then the two repeat the procedure until the air flow is withinthe desired range. Finally, the one holding up the capture hood canlower the instrument and rest. Then the team moves to the next diffuserand repeats the procedure.

With the present invention, the airflow data is collected from theShortridge meter and wirelessly radioed to the control module where acontinuously stream of readings are viewed directly by the technicianadjusting the damper. He can adjust the damper smoothly and continuouslyuntil the result is precisely at the midpoint of the desired range. Theone holding up the hood does not have to read the meter or shout to histeammate; he can concentrate on holding the hood steady. The result ofthe invention is a faster, more accurate result achieved with lesseffort and stress on the team. In many cases, the invention allows oneperson to do the same function, using a jack or prop to hold the hood inplace. This type of measurement is performed very frequently, soreducing the manpower required by about 50%, while improving theaccuracy of the results, is very important to the HVAC industry. Also,fast, accurate results help reduce the energy used in the building andcontribute to the energy goals of the country.

These system capabilities make possible new, better methods forindustrial repairs and adjustments. For instance, they eliminate theback-and-forth nature of many industrial operations where the point ofinterest is different from the point of control. Instead of a long cyclemeasurement/adjustment/measurement/etc., a real-time stream ofmeasurements is available at the point where the adjustment is beingmade, saving time and facilitating a more precise final result.

The distributed nature of the instrument in the present invention makesit possible for a technician to make the necessary measurements at thelocation of interest, transmit the measurements quickly to the locationwhere they are most needed for decisions and adjustments, which may be afew feet or hundreds of feet away. The measurement results can bedisplayed on a wrist-mounted module, a head-mounted module for heads-upviewing, or annunciated in the user's ear. The user's hands during thisprocess are free for tasks instead of being occupied by instruments.

EXAMPLES

The TAB Accelerator Kit is composed of a Wrist Reporter, Dongle, andThumbswitch. There are also accessory cables, batteries, and chargers.The Kit works in conjunction with the Shortridge AirData Multimeters,models 870C and 860C.

The Wrist Reporter is worn on the wrist of the user or otherwise placedconvenient to viewing. Readings from the meter are sent wirelessly tothe Wrist Reporter for viewing and storage. This allows the TABtechnician to finish projects more quickly with more precisemeasurements.

Example: Climb a ladder, move the ceiling tile aside, and prepare to setthe damper. Look down at your Wrist Reporter and see the flow readingschanging in real time as you move the lever. When the reading matchesyour target, you mark the lever position and/or tighten the wing nut.You're done. No more shouting back and forth to your teammate holdingthe FlowHood. The Dongle takes the reading out of the AirData Multimeterand transmits it wirelessly to the Wrist Reporter. Also, it doesn'tmatter that the viewing angle to the meter is difficult when theFlowHood is overhead. The view that matters is the view of the WristReporter.

Example: Cut 50% off the time required to perform a duct traverse byfreeing your hands of the ADM and by seeing velocity statistics as youproceed. Prepare the duct and pitot tube or AirFoil as usual. Then placethe ADM-870C in the correct measurement mode and set it to AUTO or TRENDso it reads continuously. You no longer need to crane your head to seethe meter's display. Hang it on your hip using belt loops. Place theWrist Reporter on the inside of your Wrist Reporter. Place theThumbswitch on your finger. Now use both hands to position the probe asappropriate. When the position is correct and the measurement on yourWrist Reporter looks valid, press the Thumbswitch button to store theresult. As you progress through the matrix of points, the Wrist Reporterautomatically shows you the current average velocity, along with theminimum and maximum readings of the traverse.

Alternative Embodiments

The temperature sensing elements used may be 2252-ohm thermistors,10K-ohm thermistors, thermocouples, or other type of temperature sensor.The enclosure may be plastic or metal. Batteries may vary.

The General Purpose Sensor Module is configured for use with a varietyof sensing probes, both analog and digital, to measure air and watertemperatures, humidity, CO, CO2, light intensity, and other parameters.

Summary of System-Related Functions and Innovations

The present invention is a system of modules as described above thatsolves or minimizes long-standing industry problems. A wireless networkof specialty sensors and a wearable control module allows getting datafrom the point of measurement to the point of control, and by improvingcommunication among team members.

The present invention offers a large increase in productivity byallowing a technician to move around, climb a ladder, drill a hole,adjust a damper or valve, speed up a pump, or otherwise use his handsand feet to implement changes while knowing the immediate effects ofthose changes. Multiple team members can each wear a Control Module sothey can each receive and view the measurement data directly, whichpromotes better teamwork and higher productivity. FIG. 25 shows adiagram of parts of the present invention.

These system capabilities make possible new, better methods forindustrial repairs and adjustments. For instance, they eliminate theback-and-forth nature of many industrial operations where the point ofinterest is different from the point of control. Instead of a long cyclemeasurement/adjustment/measurement/etc., a real-time stream ofmeasurements is available at the point where the adjustment is beingmade, saving time and facilitating a more precise final result. Thedistributed nature of the instrument in the present invention makes itpossible for a technician to make the necessary measurements at thelocation of interest, transmit the measurements quickly to the locationwhere they are most needed for decisions and adjustments, which may be afew feet or hundreds of feet away. The measurement results can bedisplayed on a wrist-mounted module, a head-mounted module for heads-upviewing, or annunciated in the user's ear. The user's hands during thisprocess are free for tasks instead of being occupied by instruments.

The wireless modules of the present invention provide for many differentfunctions in different applications that previously were not possible oronly possible by utilizing multiple instruments. For instance, thepresent invention includes a mobile, wrist-mountable module that candisplay two or more measurements simultaneously from different sensorsin different locations and store them with the time and date of thereadings. These new functions produce huge benefits for several HVACapplications. They give the technician the ability to see all of therelated information at the time that he is making a decision about arepair or adjustment.

The present invention combines two operating modes that were previouslyonly available in different instruments. One is a diagnostic ordebugging mode used by a technician to discover and promptly fixproblems. The other is a monitoring or datalogging mode which collectsmeasurements regularly from distributed sensors over a period of hours,days, or weeks. The data is analyzed later, usually plotted against timeto show relationships between events.

The present invention allows a mobile module to display the results in adiagnostic mode from sensors that are also at the same time part of adatalogging network.

Alternative Embodiments

While the invention has been described with reference to specificembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the true spirit and scope of theinvention. In addition, modifications may be made without departing fromthe essential teachings of the invention.

I claim:
 1. A system for displaying the results of multiple measurementsof air and water properties from separate and remote sensors, comprising(a) a control module comprising a display and a wireless transceiver;and (b) a plurality of sensor modules, wherein each sensor modulecomprises sensing means and a wireless transceiver.
 2. The system ofclaim 1 in which measurement results of multiple types from multiplelocations is available to the user on the same display screen forcomparing and contrasting and achieving the best understanding about thestatus of the environment as quickly as possible.
 3. The system of claim1 in which measurement data are available to the user on head-mounteddisplays and/or annunciated by headphones or earbuds.
 4. The system ofclaim 1 in which the user can store data in the control modulewirelessly by closing a remote switch on a separate module rather thanreaching to touch the control module's keypad.
 5. The system of claim 1in which the user can control key aspects of the system by voicecommands.
 6. The system of claim 1 in which multiple team members canuse display and/or audio modules to see or hear the same data ascoworkers.
 7. The system of claim 6 in which team members can receiveinformation via wearable display and/or audio modules for wrist, head,or elsewhere on their body as is convenient to the task at hand.
 8. Thesystem of claim 1 in which the same wireless method as is used totransmit the measurement results can also be used to transmit voicesfrom one wireless module to another like a walkie-talkie.
 9. The systemof claim 1 in which data can be stored manually or automatically atuser-set intervals or automatically at the fastest rate offered by eachparticular sensor.
 10. The system of claim 1 in which all of the datarequired for a particular application is gathered and presented to theuser concurrently for viewing and/or storage.
 11. The system of claim 1in which the sensors have mechanisms for attachment to specific buildingfixtures for indefinite in-situ measurements.
 12. Apparatus forperforming a duct traverse, comprising (a) a grip part for holdingtraditional Pitot tubes, and (b) an electronics sensing part integratedinto the grip part, and (c) means for collecting duct temperature andhumidity data via the system in (1) for adjusting the velocitycalculations for different air densities, and (d) means for measuringduct velocity and duct static pressure simultaneously, and (e) means fordisplaying velocity, pressure, temperature, humidity, density, ductsize, and airflow nearly simultaneously via the system in (1). 13.Apparatus for measuring face velocity, comprising (a) traditionalgrid-type probe having leading edge and trailing edge pressure plenums,and (b) an electronic pressure sensing module having means of attachmentand connection to said plenums without dangling tubes, and (c) a gripfor holding grid-type probe at the ideal height for user visibility, and(d) the system in (1) for collecting and providing temperature,humidity, and density data to the user along with velocity data. 14.Apparatus for measuring airflow at diffusers, comprising (a) capturehood with skirt, base, and grid-type probe having leading edge andtrailing edge pressure plenums, and (b) an electronic pressure sensingmodule having means of attachment and connection to said plenums, and(c) the system in (1) for collecting and including actual values oftemperature and optionally humidity as well as barometric pressure inthe equation used to calculate velocity and airflow, and (d) the systemin (1) for providing the user with optional displays which include allof the information required by the application, including temperature,humidity, barometric pressure, and density, as well as airflow, and (e)the system in (1) for making continuous measurements from one or moreair inlets or outlets in multiple locations and displaying them at thepoint of control, together with other information of interest such asduct static pressure and room-to-room differential pressure.